Apparatus for producing from endless fibers a card sliver suitable for drawing



Nov. 14, 1939. KA SCHMn--r 2,180,172

APPARATUS FOR PRODUCING FROM ENDLESS FIBERS A GARD sLIvER SUITABLE FORDRAWING Filed Dec. 24, 1938 .7m/enfer:

www fa Patented Nov. 14, 1939 PATENT OFFICE I APPARATUS FOR PRODUC'INGFROM END- LESS FIBERS A CARD SLIVER SUITABLE FOR DRAWING Karl JosefSchmitt, Chemnitz, Germany, assignor to Schsische Text'ilmaschinenfabrikvorm. Rich. Hartmann Aktiengesellschaft, Chemnitz, Germany, acorporation I Application December 24, A1938, Serial No. 247,700 InGermany February 5, 1938 4 Claims.

This invention relates to a method of producing from endless artificialfibers a continuous card sliver suitable for drawing.

Various methods have been proposed for this purpose but in practice theypossess'more or less objections or are entirely impracticable.

According to yone of the known proposals the bers of the sliver are cutby a cutting cylinder with narrow mutually displaced knives in such amanner that the pieces of fiber, owing to the cuts distributed over theWidth of the sliver, preserve a certain cohesion. Owing to the smoothcut surfaces of the sliver pieces it is, however, not possible to shiftthe bers separately and successively in a drawing apparatus but thepieces Aof the sliver as such are shifted. 'Ihe sliver leaving thedrawing apparatus consequently is of very unequal thickness so thatseveral doublings are necessary to obtain the necessary 1miformity.

For the purpose of avoiding the abovementioned disadvantages the endlesssliver is pierced, according to the invention, by means of needles orthe like in such a manner that the fibers are cut individually or almostindividually, the sliver being held taut at the cutting point by pairsof rollers or the like.

An apparatus for carrying out the invention is illustrated, by way ofexample, in the accompanying drawing in which:

Fig. 1 shows the apparatus in side elevation,

Fig. 2 is a front view thereof.

The artificial bers fed in an endless sliver from the articial silkspinning machine are stretched between two pairs of rollers a and b.Above this point a comb d is arranged which is vertically guided andmoved up and down by a shaft e through the intermediary of an eccentricf. The needles of the comb d are of such shape, that they cut the fibersas far as possible individually or approximately individually. The spacebetween the piercing point and the clamping point of the pair of rollersb is smaller than the length of staple.

To enable the needles to pierce the sliver at points distributed overthe entire width, the comb d is shifted after each stroke a very shortdistance @A00 to tos of a millimetre) by means of a cam g which isdriven from the shaft e through the intermediary of a worm gear h. Thecam g preferably formed 0f spirals, firmly bears against the surface kunder the iniluence of a spring i, so that the shaft e is shifted inlateral direction together with the comb d. This is effected verygradually, the piercing operations of the Comb taking place in Veryrapid succession. Owing to the step at the end of one of the spirals ofthe cam, the comb is precipitately returned to the right into itsinitial position, under the influence of the spring z', as soon as thelateral movement imparted to the comb by the spiral is terminated. Theratio between the comb movement and that of the sliver movement must bechosen according to the desired length of staple.

It is advantageous, to supportthe sliver in closest proximity to thepiercing points, that is between the pairs of rollers a and b, by a.table m provided with a notch or recess, so that stretching of the bersis avoided during the cutting operation or can only take place in directproximity to the piercing point.

On theouter side of the pair of rollers b another pair of rollers c isarranged, these rollers being driven at a higher speed than the rollersb and serving to tear the bers which are not separated by the comb d.

The needles of the comb may be blunt, very sharp, serrated, hook-shapedor similarly shaped.

The slivers delivered from several apparatus of the type described aredoubled and stretched in a normal drawing frame and condensed at o, L.by a revolving tube or roller rubbers and finally formed into a lap p.

I claim:

1. An apparatus for producing from endless fibers a sliver suitable fordrawing, comprising in combination two pairs of sliver stretchingrollers, a comb vertically reciprocated between said pairs of rollers topierce the sliver stretched between said rollers, and means forlaterally shifting said comb after every effective stroke.

2. An apparatus for producing from endless fibers a sliver suitable fordrawing, comprising in combination two pairs of sliver stretchingrollers, a comb vertically reciprocated between said pairs` of rollersto pierce the sliver stretched between said rollers, a cam disc formedby at least one spiral race bearing against said comb and adapted togradually displace the same laterally after each eii'ective stroke, andmeans for precipitately returning said comb into its initial position atthe end of its lateral displacement.

3. An apparatus for producing from endless fibers a sliver suitable fo'rdrawing, comprising in combination two pairs of sliver stretchingrollers, a comb vertically reciprocated between said pairs of rollers topierce the sliver stretched between said rollers, and means forlaterally shifting said comb after every effective stroke, the distancebetween the second pair of rollers and the piercing point being shorterthan the desired length oi staple.

4. An apparatus for producing from endless bers a. sliver suitable fordrawing, comprising 5 in combination two pairs of sliver stretchingrollers, a. comb vertically reciprocated between said pairs of rollersto pierce the sliver stretched between sad rollers, means for laterallyshitting said comb after every effective stroke, and a. table under saidcomb adapted to support the sliver in proximity to the piercing point.

KARL JOSEF SCHMITT.

